Building a Modern Pneumatic Airgun

Gallery, Projects and General > Project Logs

<< < (9/15) > >>

Dean W:
Great thread you have here, Stot. I've thought about building an air rifle a few times, but it always gets
pushed aside for engine or shop projects. Being a long time shooter, both air and firearms, this build has a
lot of interest for me. Maybe I'll get to it someday. Glad you are posting up your progress.

Dean

Stot:
Another update. I made one of the bolts/pellet probe. I wasnt sure wether to make this out of steel or brass. Steel would be easier for me, I hate machining brass because I end up pulling splinters out of every appendage for days. :bang:

I had a scrap of brass big enough, and I think it will accent well with the brass valves and trigger, so I bit the bullet and made it from that. I did wear some nitrile gloves which helped a lot with the splinters. :thumbup:

The pellet probes are calibre specific, my rifles will be .22 to start with although I may convert one to .177 later. I can turn a .22 probe down to .177, but not the other way so I'll make them both .22 for now.

Very simple turning operations to make the bolt, but it will be cross drilled for a pin to be screwed into when I'm set up for milling. The bolt handle can be put on either side in my re-design for a fully ambedextrous(sp?) operation.

* Chucked up the rough brass I had and turned it down to the same diameter as my barrels. This means I just need to drill one size hole through the breech block.
* Turned it around, parted it off and turned it down to just under the barrel bore size.
* Turned down the tip of the probe that will push the pellet past the barrel transfer port.
* Polished it up a bit.
* Turned it around again and made a threadded hole for the bolt handle bolt.

You can see where ive marked for an o-ring on the end of the probe to seal the barrel when cocked, but Im not sure what o-ring ill be using yet so ill cut the groove when I have the o-ring.

Cheers
Stot

Stot:
This week I ar bin mostly turnin'. Well that and a little case hardnening.

The ridge on the hammers makes up part of the sears in the trigger, so it makes sense to harden them so they don't wear easily. The steel I had was EN1A So case hardening it is the only way to go. Also the tip of the hammer is an adjustable screw and as this is what will take the brunt of the impact force so hardening the threads is sensible too.

I wasnt sure if I was going to get the hammers hot enough with just a propane/butane blow torch but it came up a very nice cherry red. I cant file or scribe them when done so jobs a good un. :dremel: You dont get a real sense of the red of the metal in the photos because of the flash but here you go.

* Heated up the hammer until cherry red.
* Dip in hardening compound.
* Keep red hot for 5 mins minimum.
* Quench in water.

Its easy to do really. I turned them around and did the skirt end of the hammer too as the trigger sears will rub along them during the cocking stroke and i don't want them to wear. The hammers will be polished back up before use.

Cheers
Stot

Stot:
The Turning I have done was the hammer tube end caps. These dont screw in, they are held in place by a bolt from underneath that also holds the trigger block on. Basic slip fit caps really.

This is the penultimate bit of turning, last thing is to drill through the breech block for the barrel and bolt and then ill set the lathe up for milling. :zap:

* Chucked some brass stock the same as the valves were made from.
* Turn down to slip fit the hammer tube.
* Chamfer the edges and polish up a bit with wet and dry and some scotch brite pad.
* Part off.
* Mount the part in the lathe and face off to size.
* Chamfer the back of the cap to taste. Polish this end.

And a couple of pictures of all the parts so far. :)

Cheers
Stot

cfellows:
Nice progress, Stot. I'm particularly impressed with your finish on everything. By they way, what kind of gloves are you wearing, and why? Just wondered if that's something I should consider?

Chuck

Navigation

 Message Index

Go to full version